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J A Gavigan

Publications and source records attributed to J A Gavigan.

6 recordsLinked to original sources
PubMed1999

Regulation of polyphosphate kinase gene expression in Acinetobacter baumannii 252.

A strain of Acinetobacter baumannii cultured in butyric acid media was found to take up phosphate following a period of phosphate release. PCR was used to clone the polyphosphate kinase (ppk) gene from the strain. The promoter for the ppk gene was functional in the heterologous Escherichia coli host. Using RT-PCR, transcription of the ppk gene was found to be regulated by phosphate concentration.

5' Untranslated Regions↗
PubMed1997

Isolation by genetic labeling of a new mycobacterial plasmid, pJAZ38, from Mycobacterium fortuitum.

In a two-step mating experiment with recipient strains of Mycobacterium smegmatis, the Mycobacterium fortuitum cryptic plasmid pJAZ38 was isolated. Plasmid pJAZ38 was genetically labeled by cointegration formation mediated by the kanamycin-resistant mycobacterial transposon Tn611. The region responsible for replication of pJAZ38 was located and sequenced. This region showed homology with the Mycobacterium avium plasmid pLR7 and the Mycobacterium scrofulaceum plasmid pMSC262, a family of plasmids which have been found to be widespread throughout the mycobacteria. Further experiments showed pJAZ38 to be stably inherited in the absence of selection pressure and compatible with the most commonly used mycobacterial replicon, pAL5000. In contrast to pLR7 and pMSC262, pJAZ38 was able to replicate in M. smegmatis mc(2)155, making it a useful tool for mycobacterial genetics.

Amino Acid Sequence↗
PubMed1995

Use of conjugative and thermosensitive cloning vectors for transposon delivery to Mycobacterium smegmatis.

Conjugative, thermosensitive shuttle plasmids capable of transfer from Escherichia coli to Mycobacterium smegmatis were constructed. They contain both an E. coli replicon and a thermosensitive derivative of the pAL5000 mycobacterial replicon. Using a temperature shift protocol, the conjugative plasmid, pJAZ11 was used to deliver the transposon Tn611 from E. coli into the chromosome of M. smegmatis. Analysis of transconjugants revealed the random insertion of the transposon.

Cloning, Molecular↗
PubMed1995

Differentiation by molecular typing of Mycobacterium bovis strains causing tuberculosis in cattle and goats.

Forty Mycobacterium bovis isolates from cattle and goats were analyzed by using different repetitive genetic markers. The 23 M. bovis strains from goats were found to carry six to eight copies of the insertion sequence IS6110. In contrast, most of the bovine isolates contained only a single copy of this element. The standardized IS6110 fingerprinting by restriction fragment length polymorphism (RFLP), described for Mycobacterium tuberculosis strains, allowed the differentiation of caprine strains. Although this method was not useful for typing bovine isolates, the repetitive elements pTBN12 and DR proved to be suitable for this purpose. A procedure using PCR which amplifies IS6110 in the outward direction was found to be as sensitive as RFLP for typing M. bovis strains from goats. The use of PCR and RFLP methods based on the IS6110 polymorphism would be useful for epidemiological studies of caprine tuberculosis. The results are consistent with different strains of M. bovis being implicated in bovine and caprine tuberculosis.

Animals↗